1. Field of the Invention
The invention relates to vehicular suspension system with an apparatus for the measurement of the acceleration of suspended and/or non-suspended vehicle parts or the relative acceleration between suspended and non-suspended vehicle parts with integrated acceleration sensors disposed in hydraulic, pneumatic or hydropneumatic aggregates such as vibration absorbers, pneumatic springs and hydropneumatic suspensions.
2. Description of the Prior Art
Suspension systems are known from, for example, U.S. Pat. No. 4,483,546, entitled "Self-Levelling Suspension", which corresponds to German Laid Open Patent Appln. No. DE-OS 32 12 433, in which each suspension unit of a vehicle has a sensor to adjust its platform height. The sensor produces an output value which changes progressively with the platform height. The sensor is thereby used to adjust the platform height, that is, the distance between the suspended and non-suspended vehicle parts. These sensors are used to determine the distance a piston is to travel.
The prior art also includes pure accelerometers, such as in German Patent No. DE-PS 26 24 884, in which, for the measurement of the force, two opposite reflecting surfaces form a gap, whose enclosed angle can be modified by a force acting on the inert mass. As a result of a change in the gap angle, the number of reflections changes, as well as the angle of reflection, measured toward the reflecting surface, of a beam of light emitted from the light source at a determined angle, and thus the intensity of the light which falls into the light inlet opening. Such a measurement is difficult and expensive, and cannot be used without further modification on all parts of the vehicle, since it is susceptible to interference and quite sensitive.
Another example of the prior art is U.S. Pat. No. 4,477,732, entitled "Sensor For Acceleration", which has a first photoconductor disposed in a suspended body. This first photoconductor leads light into the body from an outside light source. The light is then conducted to each of three additional photoconductors when each is aligned with the first photoconductor as the body moves within a housing. At the end of each of the three additional photoconductors there is connected a photo element which converts the light falling thereon to an electrical signal which is connected into an acceleration-related signal.
All of the afore-mentioned patents are incorporated herein by reference as if fully set forth herein in their entirety.